Problem: $\left(9x - 6\right)\left(-7x - 1\right) = \ ?$
Answer: $= 9x \cdot \left(-7x - 1\right) - 6 \cdot \left(-7x - 1\right)$ $= \left( 9x \cdot -7x \right) + \left( 9x \cdot -1 \right) + \left( -6 \cdot -7x \right) + \left( -6 \cdot -1 \right)$ $= -63x^2 + \left( 9x \cdot -1 \right) + \left( -6 \cdot -7x \right) + \left( -6 \cdot -1 \right)$ $= -63x^2 + \left( -9x + 42x \right) + \left( -6 \cdot -1 \right)$ $= -63x^2 + 33x + \left( -6 \cdot -1 \right)$ $= -63x^2 + 33x + 6$